Wood stain



United States Fatal:

3,016,279 WOOD STAIN Walter H. Lawin, Ashland, Wis. (Hayward, Wis.) N Dravfing. Filed Jan. 7, 1959, Ser. No. 785,310 1 Claim. (Cl. 8--6.5)

The present invention generally relates to a process for treating White sapwood of certain trees, such as birch, in order to stain the sapwood so that the sapwood will have the appearance of heartwood.

There is a large demand for the heartwood of the birch tree, especially in making red birch plywood and in many other uses. However, there is only a limited amount of red birch in each tree, since only the heartwood is red. Also, a portion of the heartwood is lost in the veneer lathe, since it cannot be cut because it receives the lathe centers. Therefore, it is the primary object of the present invention to reproduce the chemical processes of nature in tree growth which make the heartwood red and subject the white sapwood to these chemical processes thus changing the white sapwood to red heartwood.

The present invention includes two solutions which are applied to the wood and which cause chemical action for staining the white sapwood so that it appears to be reddish heartwood.

Another object of the present invention is to provide a solution for staining white sapwood which is easy to use and inexpensive, thus making the use of the solution economically feasible.

Other objects of the present invention will become apparent from the following detailed description of the invention:

Solution Number 1 consists of and is made by dissolving one 1) pound of sodium hydroxide (caustic soda) in one gallon of water. One-fourth ounce of oxalic acid is then added to this material, thus providing an aqueous solution. This solution is then applied to the woodby a brush, sponge or by dipping, with the wood being thoroughly wetted. .A chemical action will promptly take place and when the wood dries, it is brownish red and has a high alkaline content which makes the surface un-.

suitable for bonding or accepting a finish.

Solution Number 2 consists of three (3) ounces of concentrated sulphuric acid which is added to one gallon of Water. This solution is then applied in the same manner as solution Number 1 and neutralizes the alkalinity in the wood and removes the brownish tinge, thus making the formerly white sapwood have the same color characteristics as the red heartwood.

The two solutions are economical in manufacture since they employ readily available materials and almostanyone can apply the solutions to the wood.

It is understood that this invention is not confined to the particular embodiment described, the same being merely illustrative, and that this invention may be carried out in other ways within the scope of the appended claim without departing from the spirit of this invention, as it is obvious that the particular embodiment described is only one of the many that may be employed to attain the objects of this invention.

I claim:

The process of staining White sapwood to simulate red heartwood consisting of the steps of wetting the surface of white sapwood with an aqueous alkaline solution of one pound of sodium hydroxide dissolved in one gallon of water and one fourth ounce of oxalic acid, allowing the surface to dry, and neutralizing the dry alkaline surface with an aqueous acid solution.

References Cited in the file of this patent UNITED STATES PATENTS 1,781,449 Burchman Nov. 11, 1930 2,095,194 Hoche Oct. 5, 1937 2,176,763 Fortune Oct. 17, 1939 2,210,832 Bright Aug. 6, 1940 

